1. Field of the Invention
The invention relates to a paper feeding apparatus, particularly an apparatus in which a paper tray is removably mounted or retractably mounted with respect to a main body of the apparatus.
2. Description of the Related Art
Changes in temperature or humidity affect paper sheets loaded in a paper tray of a copying machine or a printer, particularly if they have been left for a long period of time. Such sheets can retain moisture or humidity, especially in their peripheral parts. In addition, expansion and contraction of the sheets can occur resulting in curling of the peripheral parts of the sheets. By this curling, the peripheral parts of the paper move out of a holding member which is provided in the paper tray, and paper jams or paper skews occur when a sheet is fed into the main body.
To solve these problems, side fences for holding both sides of paper sheets which are loaded in the paper sheet tray, and holding members (corner claws) for holding both top ends of the sheets are provided to prevent the sheets from curling. In this case, the side fences become obstacles and increase the time required to supply the paper, particularly in loading paper into the paper tray.
In Japanese Laid Open Patent No. 1-92137, a paper feeding apparatus having a paper holding member upstream of a feeding roller for holding an upper surface of paper sheets is disclosed. However, since the holding member holds only a center portion of the paper sheets loaded in a paper cassette, the holding member can not prevent the paper from curling. Further, in case of paper jams, one or more paper sheets could be damaged if an operator pulls out the paper tray to supply additional paper.